1. Field of the Invention
The present invention relates to a cleaning card particularly for a time recorder which is adapted to clean the protective glasses for both the card detecting and code reading photoelectric sending and receiving elements disposed along the card passage in the time recorder.
2. Description of the Prior Art
The conventional electronic time recorder has two functions, one of them being to perform on-off control for a motor for rotating card displacing rollers by detecting the inserting or removal of the time card into or from the card passage in the time recorder, while the other being to photoelectrically read a variety of codes in the form of punched holes which are arranged on the code columns of the time card for identifying personnel and other items. Further the time recording is provided with photoelectric sending and receiving elements which are located in an opposite location relative to the card passage to perform the above mentioned card detecting and code reading operations. On the inner walls of the card passage are formed openings through which photoelectric beams pass from the sending elements into the receiving elements, the openings each being fitted with a transparent protective glass covers respectively for the purpose of preventing the respective elements from being damaged or injured by the moving time card or having dust and other foreign materials adhered thereto.
Because of the fact that the time recorder is usually operated in such a manner that a number of personnel repeatedly insert their time card to have the predetermined printing thereon it is often recognized that the front surfaces of the protective glass pieces become contaminated with printing ink, dirty material adhered to the time card, or dust or like foreign material from the outside. It is also known that as the time recorder continues to be operated in that way, the transparency of the protective glass covers is increasingly reduced with the result that the intended card detecting and code reading cannot be performed with complete accuracy due to restrictive emission of the photoelectric beam from the sending elements and substantially decreased input into the receiving elements.
To obviate the above mentioned problem with the conventional time recorder a few measures were hitherto proposed and practiced. One of them is such that the card passage is designed in the split form so as to be simply disassembled to easily clean the front faces of the protective glass pieces every time when they become contaminated with dirty material. The other one is such that a commercial magnetic tape head cleaning plate such as a thin plastic plate with a cloth, felt or the like adhered thereon is inserted into the card passage through the card insert packet to clean the front faces of the protective glass covers.
However it is pointed out that the modified time recorder as described above has the drawbacks that the disassembled type card passage causes the time recorder to become complicated, resulting in an increased manufacturing cost, and moreover, the cleaning operation is laborious because it is necessary to open the outer cover and then disassemble the card passage prior to the cleaning operation. The latter mentioned cleaning plate also has the drawbacks that it is considerably difficult to insert the cleaning plate into the narrow card passage because it has a thickness considerably larger than that of the time card and furthermore it tends to become clogged in the card passage when inserting it by force with the result that either or both of the cleaning plate and card displacing rollers are injured or damaged.